Grandpa Song crouched down and tucked his white beard aside. He asked them to look at the healthy plant, then pointed to the exposed roots. What is different here?

These roots are outside, Tao said. Grandpa Song nodded. Roots take up water from the soil. Pulling can hurt the fine roots and loosen the earth around them. Without enough water, the leaves droop. Looking taller isn't the same as growing.

Ahe took off his hat. I meant to help, but I made things worse. Grandpa Song set the jug beside him. Now that you understand, you can try a better way. Tao shuffled over to make room for Ahe beside her.